My warmest thanks are due to Lieutenant Halleck, for his assistance as chief of staff, and I present him particularly to the notice of the colonel commanding, for the able manner in which he led on the attack on the 30th ultimo. Captain Naglee also deserves particular notice for the energetic and successful manner in which he fulfilled his instructions. On the 31st ultimo, Captain Naglee, with fifty mounted men of his company, was ordered to pursue the enemy in the direction of Magdalena Bay. He returned to La Paz on the 12th instant, having pursued the enemy very closely, capturing five prisoners and some arms. Lieutenant Halleck started for San José with a party of mounted men, consisting of one officer and twenty-five non-commissioned officers and privates, on the 5th instant, for the purpose of communicating with Captain Dupont, commanding United States sloop-of-war Cyane. He returned here on the 11th instant, having captured ten prisoners on his march, and taken a number of arms. From him I learn that the naval force at San José have thirty odd prisoners, and among others "Mauricio Castro," the self-styled political chief of Lower California. Lieutenant Selden, with a party from the Cyane, made a most opportune march on Santiago, where he captured a number of the enemy who had fled from the field of Todos Santos. Castro, who commanded the enemy's forces in the action of the 30th, was arrested near Maria Flores by the civil authorities and delivered up to Lieutenant Selden. During the stay of our main body at Todos Santos fourteen prisoners were captured; among them two sons of the reverend padre Gabriel Gonzales, officers of the Mexican forces. We left Todos Santos on the 5th instant, and arrived at this place on the 7th. The result of this short campaign has been the complete defeat and dispersion of the enemy's forces. We have captured their chief and six officers, and one hundred and three non-commissioned officers and privates; and others are daily presenting themselves to the civil authorities in different parts of the country. The captured arms have been given to those rancheros known to be friendly to the interests of the United States, for their protection. I am, sir, with much respect, your obedient servant, HENRY S. BURTON, _Lieutenant Colonel New York Volunteers_. Lieutenant W. T. SHERMAN, _Act. Ass. Adjt. Gen. Tenth Mil. Dep._ W. T. SHERMAN, _First Lieut. 3d Artillery A.A.A. General_. APPENDIX I. The following despatch from Governor Mason, gives an account of the state of affairs in Upper California, in October, 1847: HEADQUARTERS TENTH MILITARY DEPARTMENT, _Monterey, California, October 7, 1847_.